1. Field of Invention
The present invention relates to a vacuum induction melting and strip casting equipment, and more particularly to a vacuum melting and strip casting equipment for melting NdFeB rare earth permanent magnetic alloys and rare earth hydrogen storage alloys.
2. Description of Related Arts
The NdFeB rare earth permanent magnet is widely used to Electronics, electrical appliances, electrical motors and so on, and has a more extensive use. The rare earth hydrogen storage alloy is the negative electrode material of the NiMH battery. It is widely used to electric tools and hybrid electric vehicles and so on, and has a more extensive use.
In the existing NdFeB rare earth permanent magnet manufacturing processes and vacuum melting and strip casting equipments, the raw material of the rare earth permanent magnetic alloy or the raw material of the rare earth hydrogen storage alloy is put into the melting crucible of the vacuum melting and strip casting equipment, under vacuum and protective atmosphere, the raw material is heated up and molten to form the molten alloy, and then is casted to the external surface of the copper cooling roller with water-cooling to form the alloy slice via the tundish at the controllable speed, the cooled alloy slice falls on the horizontal rotational water-cooled rotation plate for the second cooling, after the alloy slice being cooled, the furnace door of the vacuum and strip casting equipment is open, and the alloy slice is taken out, and then the alloy slice is installed into the material box of the vacuum heat treatment furnace, and sent to the vacuum heat treatment furnace for vacuum heat treatment.
By exploring, it is found that in spite that compared to the prior ingoting process and equipment, the product performance of the currently used vacuum melting and strip casting process and equipment is greatly improved, the product still has a lot of problems. While producing the rare earth permanent magnetic alloy slice, due to the uneven secondary cooling, the metallurgical structure of the product has the uneven grain distributions and meticulous small grains, and α-Fe is often separated out. While producing the rare earth hydrogen storage alloy, there are small amounts of manganese precipitation. These phenomena seriously affect the performance of the product, the alloy slice needs to be vacuum heat treated after this in the vacuum heat treatment furnace for eliminating the manganese precipitation and homogenizing the grains.